Wear and abrasion resistant, high impact, iron alloy members are employed in a variety of industries. In particular, such members, elements or components are often used in rock crushing machines for crushing rocks and ore in the mining and concrete industries. One method used to crush such rock is to employ a centrifugal rock crusher, and an example of a centrifugal rock crusher is found in U.S. Pat. No. 5,533,685.
Centrifugal rock crushing apparatus typically contain cast iron impact members which throw or propel the rock against stationary members to effect crushing of the rock. For example, cast iron impellers throw the rock against stationary cast iron anvil members, both of which are subjected to repeated high force impact loading. The wear face of such members receives the greatest impact and is subject to the greatest abrasion or wear. Consequently, the type of material used to fabricate such rock crusher components is of critical importance.
Cast white iron alloys are economical to produce and are widely used in the rock crushing industry. White iron alloys have been found to be one of the more impact and wear resistance of the iron alloys. As such, however, these alloys are still subject to significant wear and abrasion in high impact applications. Rapid wear of rock crusher components significantly increases downtime and maintenance, which adds cost to the operation. Thus, it is highly desirable to provide an iron alloy member capable of withstanding high impact and yet also has increased wear resistance, particularly at the impact or wear surface.
While it is well known to form impact rock crusher components of cast white iron alloy because of its high resistance to impact failure and because of its relatively good abrasion resistance, conventional cast white iron impellers and anvils sometimes have an expected life of only 6-8 hours before they must be replaced. The useful life of rock crusher impellers can be longer, for example, as long as 40 hours, depending upon the material being crushed, but in every case, it would be desirable to increase the life of these critical rock crusher components. Replacement of rock crusher impellers and anvils requires a shut down of the rock crusher, which may last for 2-4 hours, in order to remove and replace the old impellers and anvils. White iron alloy impellers and anvils are, however, still the preferred choice for use in centrifugal impact rock crushers.